Extractor for dental crowns and bridges

ABSTRACT

An extractor for dental crowns and bridges, of the type comprising an oblong mounting plate, to the ends of which are articulately connected two elongated arms, bearing on their free ends their corresponding claws, featured by the face that the central portion of said plate has an opening in which is oscillatingly located a nucleus, and through this goes a threaded stem that on its end adjacent to the claws, has connected in ball-joint, a support piece that on its free end bears a semirigid antiskid coating, while on its opposite end, it has a commanding disc with a knurled edge, where there is a peripheric groove from which, in angularly displaced positions, protrude towards the inside of the disc, several radial holes adapted to receive, alternately, the end of a removable fine stick, forming a pressing lever, which cooperates with the above-mentioned commanding disc.

United States Patent Lozano et al.

[ Sept. 12, 1972 [54] EXTRACTOR FOR DENTAL CROWNS AND BRIDGES [72] Inventors: Gustavo Jimenez Lozano; Carlos Alberto Bosisio; Alejandro Sise Weinbaum, all of Av. Rogue Saenz Pena 760, of 719, Buenos Aires, Argentina [22] Filed: March 2, 1971 [21] App]. No.: 120,221

[52] US. Cl. ..32/43 [51] Int. Cl ..A6lc 3/16 [58] Field of Search ..32/47, 61, 43

[56] References Cited UNITED STATES PATENTS 1,756,245 4/1930 Flagstad et a1 ..32/43 Primary ExaminerRobert Peshock AttorneyMichael S. Striker [57] ABSTRACT An extractor for dental crowns and bridges, of the type comprising an oblong mounting plate, to the ends of which are articulately connected two elongated arms, bearing on their free ends their corresponding claws, featured by the face that the central portion of said plate has an opening in which is oscillatingly located a nucleus, and through this goes a threaded stem that on its end adjacent to the claws, has connected in ball-joint, a support piece that on its free end bears a semirigid antiskid coating, while on its opposite end, it has a commanding disc with a knurled edge, where there is a peripheric groove from which, in angularly displaced positions, protrude towards the inside of the disc, several radial holes adapted to receive, alternately, the end of a removable fine stick, forming a pressing lever, which cooperates with the above-mentioned commanding disc.

7 Claims, 3 Drawing Figures P'A'TE NTED m? W m wu u n [bun .7 vau fim I? I m w 4 a 0 0 M 0... mm 4 W L a Add EXTRACTOR FOR DENTAL CROWNS AND BRIDGES The present invention relates to a simple, new and practical device for taking off dental crowns and bridges, permitting the removal of such elements easily, quickly and without causing the patient excessive pain, as occurs at present using the conventional means which the odontologist has had available until now.

This extractor, due to its constructive and functional features, may be firmly maintained in the most convenient position over the crown or bridge to be taken off, and permits gradual and relatively gentle removal, without damaging the prosthesis nor the dental pieces on which said prosthesis is mounted.

To these advantages is added the extreme versatility of the device the extractor jaws are movable, to gripping exactly that size of the prosthesis to be taken off, and this assures an efficient and secure hold during the extracting operation, while the abutment is balljointed and carries a nonslipping plastic coating that assures an efficient setting and likewise avoids hurting or damaging the surface on which it rests; this arrangement ensures that, when turning the adjusting shank of the a shifting means, due to the ball joint, there is no transmission of the rotating movement, but only axial movement. In addition because of the ball-joint, the shank may be slightly tilted during the process, without affecting the operation of the arrangement. This is also obtained from the oscillating assembly of the support of the shank.

It is foreseen that it might be necessary to apply considerable force to the knob of the adjusting shank, and therefore it is provided with a peripheral groove which, going deep into the knurled surface of the knob, has at the bottom several radial holes of suitable depth in which it is possible to insert the end of a torque stick which may be used as a lever to obtain a more intensive and effective torque than that which might be attained by the fingers on the knurled surface of the knob alone.

The invention may be realized in the sizes, materials and shapes deemed most convenient for a particular use.

So that this invention may be clearly understood and so that there shall be no difliculty in putting it into practice, it will be described in detail, with reference to the attached drawings, in which:

FIG. 1 illustrates in perspective a preferred form of this invention, showing in dotted lines the movement of the gripping jaws, which end in gripping elements, and showing also in dotted lines, the arrangement of the radial holes of the knob at the end of the shank.

FIG. 2 is a side elevation view of the extractor, showing the tilting of the shank.

FIG. 3 is a view of the extractor of this invention, seen from below, that is, from the side provided with the gripping jaws.

In all the figures, the same reference numbers designate to the same or corresponding parts.

Now referring to the drawings attached, the extractor for dental crowns and bridges according to the present invention comprises a carrier 1, to opposite ends of which are articulately coupled, two elongated gripping jaws 2, 3, mounted on support pins 4, 5, the free ends of each of the jaws being formed as. claws or gripping portions 6, 7, having even or carved edges.

The central portion of carrier 1, has an opening 8', in which is pivotably mounted a threaded nut 8 supported by pins 9, such nut accommodating threaded shank 10 which carries on its one end a movable ball 11 connected to a cylindrical member 12, ending in abutment 13, preferably made of plastic material, while at the other end of the threaded shank is provided a knob 14, provided with knurled portions and a peripheral groove 15, in which are made several radial holes 16, of suitable depth, preferably six of them, but which may be more or less in number, as established in practice, and that are each adapted to receive the end of force multiplying stick 17, the stick 17 will have knurled por tions.

It will be clear that abutment 12, 13 is located intermediate the gripping elements and located above the tooth carrying the device to be removed, and that the abutment is movable laterally between a plurality of positions with reference to the gripping elements. Shifting means according to the invention comprises shank 10 and knob 14, the knob constituting twisting means.

In order to use the extractor, it isonly necessary to grip with the gripping elements the base of (crown or the like to be removed) and by rotating the knob 14, by virtue of the axial force applied by abutment 12, one obtains the axial displacement of the arrangement formed by the plate 1 and the arms 2, 3, thus obtaining gradually the desired extraction of the crown, bridge, or the like.

It is easy to understand that the present invention is not limited in any way to the embodiment described and illustrated on the contrary, modifications of shape and/or individual features may be made without departing from the scope of the invention, as set forth in the claims.

We claim:

1. A dental extractor for dislodging from a tooth a cap having a first end and a second end bounded by a circumferential edge, comprising carrier means; gripping means on said carrier means and including at least two independently pivotable transversely spaced gripping elements movable into engagement with said edge; abutment means on said carrier means intermediate said gripping elements; mounting means mounting said abutment means for lateral movement relative to said gripping elements between a plurality of positions; and moving means for moving said carrier means and gripping means relative to said abutment means in directions axially of said cap so as to at least partially dislodge the latter from an associated tooth.

2. A dental extractor as defined in claim 1, wherein said moving means comprises a shank pivotably mounted on said carrier means and having a first end portion carrying said abutment means.

3. A dental extractor as defined in claim 2, wherein mounting means is a universal joint coupling said shank with said abutment means.

4. A dental extractor as defined in claim 3, wherein said moving means includes threaded nut means pivotably mounted on said carrier means, and wherein said shank is threaded and is threadingly mounted by said threaded nut means.

5. A dental extractor as defined in claim 4, wherein said shank has a second end portion; and further comprising twisting means on said second end portion for twisting said shank.

6. A dental extractor as defined in claim 4, wherein said twisting means comprises a knob.

7. A dental extractor as defined in claim 6, wherein said moving means further includes force-multiplying means cooperating with said knob, whereby to apply an 5 increased twisting torque via said knob to said shank. 

1. A dental extractor for dislodging from a tooth a cap having a first end and a second end bounded by a circumferential edge, comprising carrier means; gripping means on said carrier means and including at least two independently pivotable transversely spaced gripping elements movable into engagement with said edge; abutment means on said carrier means intermediate said gripping elements; mounting means mounting said abutment means for lateral movement relative to said gripping elements between a plurality of positions; and moving means for moving said carrier means and gripping means relative to said abutment means in directions axially of said cap so as to at least partially dislodge the latter from an associated tooth.
 2. A dental extractor as defined in claim 1, wherein said moving means comprises a shank pivotably mounted on said carrier means and having a first end portion carrying said abutment means.
 3. A dental extractor as defined in claim 2, wherein mounting means is a universal joint coupling said shank with said abutment means.
 4. A dental extractor as defined in claim 3, wherein said moving means includes threaded nut means pivotably mounted on said carrier means, and wherein said shank is threaded and is threadingly mounted by said threaded nut means.
 5. A dental extractor as defined in claim 4, wherein said shank has a second end portion; and further comprising twisting means on said second end portion for twisting said shank.
 6. A dental extractor as defined in claim 4, wherein said twisting meanS comprises a knob.
 7. A dental extractor as defined in claim 6, wherein said moving means further includes force-multiplying means cooperating with said knob, whereby to apply an increased twisting torque via said knob to said shank. 